Cleopatra's sister Arsinoe IV fought Caesar, walked in chains in his triumph and was killed at a temple on Antony's orders, and the skeleton said to be hers was a boy's

In 48 BC, while Julius Caesar was besieged in Alexandria, Cleopatra's younger sister Arsinoe escaped the palace with her tutor, the eunuch Ganymedes, and proclaimed herself queen. She took command of the Egyptian army, had its general Achillas executed and trapped Caesar in part of the city. In 47 BC her officers handed her to Caesar in exchange for Ptolemy XIII. In 46 BC Caesar led her among the captives in his triumph in Rome. Cassius Dio writes that a woman in chains was "a spectacle which had never yet been seen" at Rome, that the crowd pitied her, and that Caesar released her. She lived as a suppliant at the temple of Artemis at Ephesus. In 41 BC Antony, at Cleopatra's urging, sent assassins who killed her. In 1929 the Austrian archaeologist Josef Keil found a skull in a water-filled sarcophagus in the Octagon, a tomb on the main street of Ephesus. The rest of the skeleton was recovered in 1982. Some scholars proposed it was Arsinoe. In January 2025 a University of Vienna team led by Gerhard Weber published DNA and radiocarbon tests in Scientific Reports. The bones were a boy's, aged about 11 to 14, with a Y chromosome and ancestry from Italy or Sardinia. Arsinoe's body has not been identified.